A free app for Android, by buddyapps.

Improve English Speaking skill is an app that provides basic knowledge of English grammar to help the users improve their communication skills. It is an offline app and you can use it anytime, anywhere after downloading the application, you no longer need an internet connection. It is designed in a simple and intuitive way that makes it easy for people to use. 

It consists of different sections that include:

The first part contains the basics of English grammar. It is divided into two sections: The first section contains the most basic elements and the second contains more advanced elements. The second part contains the practice section. This part consists of different exercises that help the users to improve their communication skills.